UIColor Utilities

UIColor+Extension.swift

import UIKit

extension UIColor {
  
  // Returns RGB(A) UIColor value from hexidecimal String representation
  // Example: let blueColor = UIColor(hexString: "006699")
  convenience init(hexString: String, alpha: CGFloat = 1.0) {
    let hexString = hexString.trimmingCharacters(in: .whitespacesAndNewlines)
    let scanner = Scanner(string: hexString)
    
    if hexString.hasPrefix("#") {
      scanner.scanLocation = 1
    }
    
    var color: UInt32 = 0
    scanner.scanHexInt32(&color)
    
    let mask = 0x000000FF
    let r = Int(color >> 16) & mask
    let g = Int(color >> 8) & mask
    let b = Int(color) & mask
    
    let red   = CGFloat(r) / 255.0
    let green = CGFloat(g) / 255.0
    let blue  = CGFloat(b) / 255.0
    
    self.init(red: red, green: green, blue: blue, alpha: alpha)
  }
  
  var hexString: String {
    
    var r: CGFloat = 0
    var g: CGFloat = 0
    var b: CGFloat = 0
    var a: CGFloat = 0
    
    getRed(&r, green: &g, blue: &b, alpha: &a)
    
    let rgb:Int = (Int)(r*255)<<16 | (Int)(g*255)<<8 | (Int)(b*255)<<0
    
    return String(format: "#%06x", rgb)
  }
  
}